You can shorten or extend in the same direction an existing pipe that has at least one open end. This technique is useful when you need to make new connections, especially if design changes to the pipeline configuration are necessary.
Click an open end of pipe.
Drag the end point of the pipe to extend or shorten it as needed, and then release the mouse button.
If the pipe bumps up against another open end, the software places a bend element, reducer, or branch element as appropriate.